What Would Happen If The Moon Cracked In Half?

The Earth has been a bit more than lucky throughout the years at avoiding giant asteroids heading our way. What if one was on course for the planet we call home but missed? What if that asteroid hit the moon hard enough that it cracked in half? It’s not something that many have considered, but it’s something we might now.

It turns out that people thought that happened in England back in 1178 when it was recorded there was a large flash on the moon before it seemingly split into two and went dark. While the moon didn’t break up, it was enough to get people wondering about what would happen if it really did happen. So, what would happen if the moon cracked in half?

The moon would likely explode instead of crack in two

Let’s start at the beginning. To have something large enough to damage the moon, it would likely have to be as large or larger than the moon itself. However, this comes with its own problems, as it would likely cause the moon to explode into thousands of pieces instead of crack in two. The world would know what’s happened right away, as it would take 1.3 seconds to see the impact from the Earth and the hurtling debris that would instantly come our way. While the moon chunks could be larger than the asteroid that wiped out the dinosaurs, they wouldn’t ever reach speeds that fast. Instead, it would likely look like an epic meteor shower with just a 1% energy release expected from asteroids of that size. 

We might not know the moon has split into two

Say the moon does get split in two instead of exploding; there’s a good chance we wouldn’t instantly know from Earth anyway. That’s because it could happen on the dark side of the moon, and we wouldn’t notice anything was wrong until gravity pulled the two sides apart. From there, it would take millions, if not billions, of years for gravity from all sides to turn these semi-spheres into the round shape we’re used to from the moon. Of course, this is if the two new moons don’t crash into each other first.

The Earth would no longer spin on its current tilt

Did you know that the Earth currently rotates on a tilt of 23.4 degrees? Losing our moon by it cracking in two would mean that we lose the gravitational pull it provides, which would quickly change the tilt of the planet. Instead, it’s likely the world would rotate at a 45-degree angle, meaning the North and South Poles would be the things pointed at the sun instead. Of course, this would mean major climate changes across the world as the sun would no longer shine on the equator. It could also cause significant ice ages every few thousand years. 

The tides would be affected by a moon split and would alter animal behavior

One of the many things people know about the moon is its effect on the planet’s tides. It works by pulling water toward the major oceans that face the moon at the time, so no longer having a complete moon would see some huge changes. For one, wild animals would have even more competition for shelter and food. The rising and falling tides have a huge effect on marine life, such as sea turtles, who use the tides during mating seasons. Losing the tides could see plenty of marine animals whipped out.

Thankfully, it doesn’t look as though the moon will crack in two any time soon. Still, it doesn’t always hurt to wonder what would happen if it came true. Thankfully, the moon has fended off the hundreds of asteroids it takes hits from every year so far, so the odds are looking good.